Half of Kids with Mental Illness Go Untreated

by John Gever John Gever,Senior Editor, MedPage Today
December 14, 2009

Action Points

Explain to interested patients that NHANES is a large, continuous government survey that collects data on a wide range of health indicators, behaviors, and risk factors.

Explain that the diagnoses reported in this study were based on interviews with parents and children but did not involve direct evaluation by psychiatrists or other mental health professionals.

Half of children and younger adolescents meeting criteria for mental disorders had not seen a health professional for their symptoms in the past year, researchers found.

Data from the National Health and Nutrition Examination Survey from 2001 to 2004 indicated that 13% of 8- to 15-year-olds had a recognized mental disorder, but only 51% of them had sought professional help, reported Kathleen Ries Merikangas, PhD, of the National Institute of Mental Health in Bethesda, Md., and colleagues.

These are the first estimates of the prevalence in children of mental disorders as defined in DSM-IV, the psychiatric profession's standard reference, the researchers wrote online in Pediatrics.

For many disorders, the NHANES data indicated lower prevalences than commonly reported, Merikangas and colleagues wrote.

"However, they are quite comparable to findings from other U.S. studies that used similar diagnostic methods and criteria and are strikingly similar to those reported for a community survey conducted at the same time in Houston, Texas," the researchers added.

They reported the following 12-month prevalences of disorders in the 8- to 15-year-old population:

Attention deficit-hyperactivity: 8.6% (SE 0.7%)

Mood disorder: 3.7% (SE 0.6%)

Conduct disorder: 2.1% (SE 0.3%)

Anxiety disorder: 0.7% (SE 0.3%)

Panic disorder: 0.4% (SE 0.1%)

Generalized anxiety: 0.3% (SE 0.1%)

Eating disorder: 0.1% (SE 0.1%)

The researchers found that attention deficit was predominant in half of children with ADHD. The other half were split evenly between those with hyperactivity-predominant features and those with mixed symptoms.

About 70% of those with mood disorders had major depression (population prevalence 2.7%, SE 0.6%), with the remainder having dysthymia (1.0%, SE 0.3%).

Overall, 13.1% (SE 0.9%) of children in the survey had one or more of these disorders. Having multiple disorders was unusual, though -- only about 15% of those with disorders had more than one, the researchers found.

The latter finding contrasts with studies in adults, which have found that multiple diagnoses are the rule, Merikangas and colleagues indicated.

Most had severe impairment. The overall prevalence of one or more disorders with severe impairment was 11.3% (SE 0.9%).

Some of the disorders showed significant differences between age groups or genders.

As expected, ADHD was about twice as common in boys than in girls, both overall and in those with severe impairment (P<0.001). Girls were about twice as likely to have mood disorders, overall and with severe impairment (P<0.05).

Mood disorders were also more common among 12- to 15-year-olds relative to younger children.

Merikangas and colleagues also reported the prevalence of mental health services usage within the previous year among those with mental disorders:

Any disorder: 50.6% (SE 3.4%)

ADHD: 47.7% (SE 4.4%)

Conduct disorder: 46.4% (SE 8.0%)

Mood disorders: 43.8% (SE 6.0%)

Anxiety disorders: 32.2% (SE 14.3%)

Remarkably, these figures were not much higher when the researchers considered only cases with severe impairment. The overall usage of services was 52.8% and, among individual categories, the figure topped 50% only for mood disorders (50.7%).

Older children and boys were somewhat more likely to receive services, with adjusted odds ratios of 1.9 (P=0.042) and 2.0 (P=0.029), respectively.

There were also trends indicating that blacks and Mexican-Americans were less likely than whites to have received treatment.

The low prevalences of most disorders meant the number of children with disorders was relatively small, despite the large sample included in NHANES, leaving the study underpowered for some potential correlations.

In the NHANES program, 3,042 children underwent personal evaluations from 2001 to 2004. These included extensive interviews as well as physical exams. The interviews were structured to collect the information required in DSM-IV for diagnosing the mental disorders reported in the current study. Some disorders, such as schizophrenia and phobias, were not included.

Parents or caregivers also provided information in the survey.

Merikangas and colleagues identified several limitations of the study:

Lack of data on certain categories of mental disorder

Reliance on one informant (parent or child) for some diagnostic information

Lack of systematic psychiatric evaluation to validate diagnoses

Despite these limitations, the researchers said the findings "will provide a valuable empirical basis for the development of health policies designed to maximize prevention efforts and to minimize the consequences of these conditions in U.S. youths."